Mars Science Laboratory is going to be HUGE

Yesterday I deposited the baby with her grandmother and went to the Jet Propulsion Laboratory for a press junket to the opening of their new Mars Yard. (I did ask if I could bring Anahita along but I guess it's too complicated to get kids under 12 access to the Lab. Too bad, I think she would have enjoyed it!)

The Mars Yard is an outdoor facility where the robotics lab test-drives their rovers. For a long time, it has been an area roughly the size of a softball infield, perfectly flat, peppered with rocks ranging in size from pebbles to a soccer ball or so. This was adequate for developing and testing the Rocky series of rovers that led to Sojourner, the subsequent FIDO and its sister rovers, and the Mars Exploration Rover, but once the rovers were on Mars the robotics lab ran into a problem: there were no sloping surfaces in the Mars Yard for test-driving. They had to truck a bunch of dirt in to the loading dock of the building where they housed the engineering model to build a slope. Clearly, the Mars Yard needed upgrading. Yesterday's opening showed us the new-and-improved Mars Yard, which was six times larger, contained much larger rocks, and included one area with a variably sloping surface.

All of which was interesting, but that wasn't the best part of the day. They used the opportunity to unveil to the press the mobility model of the next Mars rover, Mars Science Laboratory or MSL. (Although I generally try to avoid using acronyms, it's almost inevitable to call this MSL. MSL has already stood for two different things for the same mission, and Mars Science Laboratory just doesn't seem like a very good name for a rover to me, so I usually wind up calling it MSL.) We -- I and about a dozen other press and another dozen or so JPL employees and what must have been every green-badged summer intern at JPL -- were standing inside the shed on the Mars Yard, and they opened the garage door...

Emily Lakdawalla

Unveiling MSL

At the opening of the newly remodeled Mars Yard at the Jet Propulsion Laboratory on June 19, 2007, the garage door opens on the gigantic frame of the mobility model of Mars Science Laboratory.

I am forced to admit here that upon first sight of the giant spread of those wheels appearing at the door, I shouted something that will probably have to be bleeped from the TV crews' coverage of this event. Mars Science Laboratory is Absolutely Freaking HUGE.

This model is the mobility model, which is to say that it has no brain or instruments, just wheels and legs sticking out of a body that exerts the same pressure on the wheels, with the same center of gravity, as the actual rover's body will when it is on the surface of Mars. (Because it "has no brain," the engineers call this the "scarecrow.") Its features were described to us by MSL's lead mobility system engineer, Jaime Waydo. Although it is much larger than Spirit or Opportunity, the rocker-bogie mobility system appears to work exactly the same way.

Emily Lakdawalla

MSL Mobility System Engineer Jaime Waydo

At the opening of the newly remodeled Mars Yard at the Jet Propulsion Laboratory on June 19, 2007, the lead engineer on the development of MSL's mobility system, Jaime Waydo, explains how it works.

With the introductions over, they took the rover for a test drive into the new Mars Yard. Here are some photos. The aluminum wheels made impressive scraping and grinding noises as the thing was driven over rocks twice their height. On Mars, they won't risk the spacecraft by driving it over rocks this big -- they'll stick to rocks that are wheel-height (about half a meter) or smaller. First, the rover with a couple of guys for scale:

Emily Lakdawalla

The MSL 'scarecrow'

Driving over rocks:

Emily Lakdawalla

The MSL 'scarecrow'

A closeup on a wheel, and a wheel track with my feet for scale:

Emily Lakdawalla

A Mars Science Laboratory wheel

Mars Science Laboratory's wheels are nearly half a meter in diameter, almost twice the diameter of the Mars Exploration Rover wheels. The hubs connect to the rims via delicate U-shaped springs.

Emily Lakdawalla

Mars Science Laboratory wheel tracks

The tracks of the Mars Science Laboratory rover, with a pair of feet for scale. Note the "JPL" print at upper right. The actual rover will have different-looking wheel tracks.

They had lots of other rover models driving around, mostly variants on FIDO. This one, called Pluto, was showing off its ability to steer all six wheels and crab-walk at an angle:

Emily Lakdawalla

The Pluto rover

Pluto is based on the FIDO rover design. It is intermediate in size between Sojourner and the Mars Exploration Rovers. Here, it is jigging sideways with all six wheels turned. Neither Sojourner, nor Spirit and Opporutnity, nor MSL can rotate its center wheels this way.

Just for fun, I took a couple of sets of images where I moved my camera slightly from picture to picture, allowing three-dimensional views. These are cross-eyed stereo pairs; stare at one and cross your eyes until the two images overlap in the middle of your vision, then try to focus your vision to get the crossed image to resolve into three dimensions.

Emily Lakdawalla

The MSL 'scarecrow' (crossed-eye stereo)

To see the Mars Science Laboratory rover in three dimensions, look at this image and then cross your eyes until the two images overlap. The two men in the image give a sense of scale (note one is standing behind the rover and one is standing in front of the rover's hind wheel).

Finally, here is my first venture onto YouTube, with some video of the rover in motion. I apologize for the very low quality of these videos! I'll try to do better next time.

Emily Lakdawalla

Mars Science Laboratory rolls over a large rock (part 1)

The rover's rocker-bogie suspension system has little difficulty negotiating rocks that are twice the diameter of its wheels (Part 1 of 2). Recorded at the opening of the newly remodeled Mars Yard at the Jet Propulsion Laboratory on June 19, 2007, the "scarecrow" model of Mars Science Laboratory (so named because it "has no brain") is put through its paces. It was demonstrated to have no difficulty climbing meter-sized boulders, but to avoid risk the actual rover will not be driven over rocks taller than its wheels while on Mars.

Emily Lakdawalla

Mars Science Laboratory rolls over a large rock (part 2)

The rover's rocker-bogie suspension system has little difficulty negotiating rocks that are twice the diameter of its wheels. (Part 2 of 2) Recorded at the opening of the newly remodeled Mars Yard at the Jet Propulsion Laboratory on June 19, 2007, the "scarecrow" model of Mars Science Laboratory (so named because it "has no brain") is put through its paces. It was demonstrated to have no difficulty climbing meter-sized boulders, but to avoid risk the actual rover will not be driven over rocks taller than its wheels while on Mars.

Emily Lakdawalla

Mars Science Laboratory wheels roll over rocks

Two wheels scrape across a 50-centimeter-high boulder. Recorded at the opening of the newly remodeled Mars Yard at the Jet Propulsion Laboratory on June 19, 2007, the "scarecrow" model of Mars Science Laboratory (so named because it "has no brain") is put through its paces. It was demonstrated to have no difficulty climbing meter-sized boulders, but to avoid risk the actual rover will not be driven over rocks taller than its wheels while on Mars.

Emily Lakdawalla

Mars Science Laboratory turns, rolls, climbs a rock

Here, it turns in place, then rolls forward a little, with one wheel climbing up a rock. Note that the body doesn't tilt at all as the wheel climbs the rock. Recorded at the opening of the newly remodeled Mars Yard at the Jet Propulsion Laboratory on June 19, 2007, the "scarecrow" model of Mars Science Laboratory (so named because it "has no brain)" is put through its paces. It was demonstrated to have no difficulty climbing meter-sized boulders, but to avoid risk the actual rover will not be driven over rocks taller than its wheels while on Mars.